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1.
J. C. Senkbeil D. M. Brommer P. G. Dixon M. E. Brown K. Sherman-Morris 《Natural Hazards》2010,54(1):141-158
Hurricane evacuations in the United States are costly, chaotic, and sometimes unnecessary. Many coastal residents consider
evacuation after viewing a forecasted graphic of where the storm is anticipated to make landfall. During the evacuation process,
hurricane tracks commonly deviate from the forecasted landfall track and many evacuees may not pay attention to these track
deviations after evacuating. Frequently, a disconnect may occur between the actual landfall track, the official forecasted
track, and the perceived track of each individual as they made their evacuation decision. Specifically for evacuees, a shift
in track may decrease the hazards associated with a landfalling hurricane since evacuees perceive their threat level to be
high at the time of evacuation. Using survey data gathered during the evacuation from Hurricane Gustav (2008) in coastal Louisiana
(USA), we calculated a type of Z-score to measure the distance error between each evacuee’s perceived landfall location and the actual landfall location from
each evacuee’s home zip code. Results indicate a personal landfall bias in the direction of home zip code for evacuees of
three metropolitan regions. Evacuees from the greater New Orleans area displayed the highest error, followed by evacuees from
greater Lafayette. Furthermore, we validate the authenticity of the previous results by employing two additional methods of
error assessment. A large regional error score might possibly be a predictor of evacuation complacency for a future hurricane
of similar magnitude, although there are many other variables that must be considered. 相似文献
2.
This article describes the challenges confronting local authorities who must decide if and when to initiate evacuations from
tropical cyclones. This problem can be decomposed into the behavior of the hurricane that is relevant to evacuation and the
behavior of evacuees that is relevant to the hurricane. The uncertain behavior of these two systems can be modeled in an evacuation
management decision support system (EMDSS). The hurricane EMDSS described here displays information about the minimum, most,
and maximum probable evacuation time estimates (ETEs) in comparison to the earliest, most, and latest probable estimated times
of arrival (ETAs) for storm conditions. In addition, EMDSS calculates the cost of false positive (the economic cost of an
evacuation) and false negative (lives lost in a late evacuation) decision errors. EMDSS is being used in experiments to assess
different information displays, team compositions, community characteristics, and hurricane scenarios. In addition, it will
be used in training and actual hurricane operations. Finally, definition of the program’s requirements has identified further
research needed to build a better empirical base for its input data. 相似文献
3.
4.
J. Birkmann P. Buckle J. Jaeger M. Pelling N. Setiadi M. Garschagen N. Fernando J. Kropp 《Natural Hazards》2010,55(3):637-655
Disaster associated with natural hazards can lead to important changes—positive or negative—in socio-ecological systems. When
disasters occur, much attention is given to the direct disaster impacts as well as relief and recovery operations. Although
this focus is important, it is noteworthy that there has been little research on the characteristics and progress of change
induced by disasters. Change, as distinct from impacts, encompasses formal and informal responses to disaster events and their
direct and indirect impacts. While smaller disasters do not often lead to significant changes in societies and organizational
structures, major disasters have the potential to change dominant ways of thinking and acting. Against this background, the
article presents an analytical framework for distinguishing change from disaster impacts. Drawing from research in Sri Lanka
and Indonesia, formal and informal changes after the Indian Ocean Tsunami of 2004 are examined and discussed against the background
of the conceptual framework. The changes examined range from the commencement of the peace process in Aceh, Indonesia, to
organizational and legal reforms in Sri Lanka. The article concludes that change-making processes after disasters need to
be understood more in depth in order to derive important strategic policy and methodological lessons learned for the future,
particularly in view of the increasing complexity and uncertainty in decision making due to climate change. 相似文献
5.
Marcos A. E. Chaparro Mauro A. E. Chaparro Claudia Marinelli Ana M. Sinito 《Environmental Geology》2008,54(2):365-371
Several statistical analyses—as alternative tools—were applied to magnetic monitoring studies. Magnetic and chemical data
from two environments have been gathered from previous papers and studied separately. Univariate and multivariate analyses
were first examined, revealing a link between magnetic and chemical variables. The latter analyses, in particular, canonical
correlation analysis, showed very good canonical correlations: R = 0.950 (Antarctica) and R = 0.891 (Argentina). On the other hand, in order to classify the data according to the degree of contamination, principal
coordinates and discriminant analyses, as well as the comparison of several multivariate means were performed. Three groups
were distinguished in both case studies, which were well classified at a low margin of error and quite different from each
other at a significant level: 0.01 (Antarctica) and 0.05 (Argentina). The joint use of these statistical analyses also showed,
in agreement with previous studies, that the relevant variables in order to identify atmospheric pollution are: magnetic susceptibility,
saturation of isothermal remanent magnetisation, anhysteric susceptibility/magnetic susceptibility, remanent coercivity, and
copper, lead, zinc and chromium contents. 相似文献
6.
An isotope-geochronological study has been performed to examine the products of Late Cenozoic collision volcanism on the northern
coast of Lake Van, Turkey. We obtained 45 new K—Ar dates, based on which the principal time characteristics of volcanic activity
in the region have been determined. Volcanic activity in the northern coast of Lake Van has lasted ∼15 myr; it has had an
expressed discrete nature, when periods of intense volcanic activity alternated with long-lasting pose periods. Four stages
of Neogene—Quaternary volcanism have been identified: Middle Miocene (15.0—13.5 Ma), Late Miocene (10—9 Ma), Pliocene (5.8—3.7
Ma), and Quaternary (1.0—0.4 Ma). The average duration of the stages was 1—2 myr; the stages were separated from each other
with periods of inactivity of approximately equal lengths (∼3 myr). For each of the Pliocene and Quaternary stages, three
additional phases of volcanism have been identified, which were separated from each other with short time intervals (a few
hundred thousand years). The last burst of volcanic activity in the study area occurred ∼400 ka; similar to Quaternary volcanism
in general, it was not characterized by a high intensity. An important result of the studies performed was to confirm the
existence of a separate Middle Miocene stage of collision volcanism for the Caucasian—Anatolian Segment of the Alpine Fold
Belt. New geochronological data generated presented in this paper indicate that Neogene—Quaternary volcanism in this portion
of the belt started much earlier (∼15 Ma) than assumed by the majority of the previous researchers. 相似文献
7.
Identifying wildland fire ignition factors through sensitivity analysis of a neural network 总被引：6，自引：2，他引：4
Christos Vasilakos Kostas Kalabokidis John Hatzopoulos Ioannis Matsinos 《Natural Hazards》2009,50(1):125-143
Artificial neural networks (ANNs) show a significant ability to discover patterns in data that are too obscure to go through
standard statistical methods. Data of natural phenomena usually exhibit significantly unpredictable non-linearity, but the
robust behavior of a neural network makes it perfectly adaptable to environmental models such as a wildland fire danger rating
system. These systems have been adopted by many developed countries that have invested in wildland fire prevention, and thus
civil protection agencies are able to identify areas with high probabilities of fire ignition and resort to necessary actions.
Since one of the drawbacks of ANNs is the interpretation of the final model in terms of the importance of variables, this
article presents the results of sensitivity analysis performed in a back-propagation neural network (BPN) to distinguish the
influence of each variable in a fire ignition risk scheme developed for Lesvos Island in Greece. Four different methods were
utilized to evaluate the three fire danger indices developed within the above scheme; three of the methods are based on network’s
weights after the training procedure (i.e., the percentage of influence—PI, the weight product—WP, and the partial derivatives—PD
methods), and one is based on the logistic regression (LR) model between BPN inputs and observed outputs. Results showed that
the occurrence of rainfall, the 10-h fuel moisture content, and the month of the year parameter are the most significant variables
of the Fire Weather, Fire Hazard, and Fire Risk Indices, respectively. Relative humidity, elevation, and day of the week have
a small contribution to fire ignitions in the study area. The PD method showed the best performance in ranking variables’
importance, while performance of the rest of the methods was influenced by the number of input parameters and the magnitude
of their importance. The results can be used by local forest managers and other decision makers dealing with wildland fires
to take the appropriate preventive measures by emphasizing on the important factors of fire occurrence. 相似文献
8.
Simultaneous parameter identification of a heterogeneous aquifer system using artificial neural networks 总被引：2，自引：1，他引：1
An artificial neural network (ANN) model is proposed for the simultaneous determination of transmissivity and storativity
distributions of a heterogeneous aquifer system. ANNs may be useful tools for parameter identification problems due to their
ability to solve complex nonlinear problems. As an extension of previous study—Karahan H, Ayvaz MT (2006) Forecasting aquifer
parameters using artificial neural networks, J Porous Media 9(5):429–444—the performance of the proposed ANN model is tested
on a two-dimensional hypothetical aquifer system for transient flow conditions. In the proposed ANN model, Cartesian coordinates
of observation wells, associated piezometric heads and observation time are used as inputs while corresponding transmissivity
and storativity values are used as outputs. The training, validation and testing processes of the ANN model are performed
under two scenarios. In scenario 1, all the sampled data are used through the simulation time. However, in the scenario 2,
there are data gaps due to irregular observations. By using the determined synaptic network weights, transmissivity and storativity
distributions are predicted. In addition, the performance of the proposed ANN is tested for different noise data conditions.
Results showed that the developed ANN model may be used in simultaneous aquifer parameter estimation problems. 相似文献
9.
Almost all engineering evacuation models define the objective as minimizing the time required to clear the region or total
travel time, thus making an implicit assumption that who will or should evacuate is known. Conservatively evacuating everyone
who may be affected may be the best strategy for a given storm, but there is a growing recognition that in some places that
strategy is no longer viable and in any case, may not be the best alternative by itself. Here, we introduce a new bi-level
optimization that reframes the decision more broadly. The upper level develops an evacuation plan that describes, as a hurricane
approaches, who should stay and who should leave and when, so as to minimize both risk and travel time. The lower level is
a dynamic user equilibrium (DUE) traffic assignment model. The model includes four novel features: (1) it refocuses the decision
on the objectives of minimizing both risk and travel time; (2) it allows direct comparison of more alternatives, including
for the first time, sheltering-in-place; (3) it uses a hurricane-scenario-based analysis that explicitly represents the critically
important uncertainty in hurricane track, intensity, and speed; and (4) it includes a new DUE algorithm that is efficient
enough for full-scale hurricane evacuation applications. The model can be used both to provide an evacuation plan and to evaluate
a plan’s performance in terms of risk and travel time, assuming the plan is implemented and a specified hurricane scenario
then actually occurs. We demonstrate the model with a full-scale case study for Eastern North Carolina. 相似文献
10.
Formation and characteristics of post-earthquake debris flow: a case study from Wenjia gully in Mianzhu, Sichuan, SW China 总被引：3，自引：0，他引：3
H. Y. Ni W. M. Zheng Y. B. Tie P. C. Su Y. Q. Tang R. G. Xu D. W. Wang X. Y. Chen 《Natural Hazards》2012,61(2):317-335
During the three flood seasons following the Wenchuan earthquake in 2008, two catastrophic groups of debris flow events occurred
in the earthquake-affected area: the 2008-9-24 debris flow events, which had a serious impact on rebuilding; and the 2010-8-13/14
debris flow events, which destroyed much of the progress made in rebuilding. The Wenjia gully is a typical post-earthquake
debris flow gully and at least five debris flows have occurred there. As far as the 2010-8-13 debris flow is concerned, the
deposits of the Wenjia gully debris flow reached a volume of 3.1 × 106 m3 in volume and hundreds of newly built houses were buried. This study took the Wenjia gully debris flow as an example and
discussed the formation and characteristics of post-earthquake debris flow on the basis of field investigations and a remote
sensing interpretation. The conclusions drawn from the investigation and analysis were as follows: (1) Post-earthquake debris
flows were a joint result of both the earthquake and heavy rainfall. (2) Gully incision and loose material provision are key
processes in the initiation and occurrence of debris flows and a cycle can be presented as the following process: runoff—erosion—collapse—engulfment—debris
flow—further erosion—further collapse—further engulfment—debris flow enlargement. (3) The amount of rainfall that triggered
debris flows from the Wenjia gully was significantly less than the average daily rainfall, while the intraday rainfall threshold
decreased by at least 23.3%. (4) The occurrence mechanism of Wenjia gully debris flow was an erosion type and there was a
positive relationship between debris flow magnitude and rainfall, which fitted an exponential model. (5) There were five representative
characteristics of Wenjia gully debris flow: the long duration of the occurring process; the long distance of deposition chain
conversion during the process of damage; magnification in the scale of debris flow; and the high frequency of debris flow
events. 相似文献
11.
When planning a TBM drive in squeezing ground, the tunnelling engineer faces a complex problem involving a number of conflicting
factors. In this respect, numerical analyses represent a helpful decision aid as they provide a quantitative assessment of
the effects of key parameters. The present paper investigates the interaction between the shield, ground and tunnel support
by means of computational analysis. Emphasis is placed on the boundary condition, which is applied to model the interface
between the ground and the shield or tunnel support. The paper also discusses two cases, which illustrate different methodical
approaches applied to the assessment of a TBM drive in squeezing ground. The first case history—the Uluabat Tunnel (Turkey)—mainly
involves the investigation of TBM design measures aimed at reducing the risk of shield jamming. The second case history—the
Faido Section of the Gotthard Base Tunnel (Switzerland)—deals with different types of tunnel support installed behind a gripper
TBM. 相似文献
12.
Prof. Dr. Borchert Günter 《GeoJournal》1992,26(3):259-263
Instructions concerning factor analysis, complex analysis, system analysis, trend analysis and sensitive analysis are given.
Their validity for geographical investigations and research work with integrated spatial approach is discussed. Objective
are calculations and abstract results; the demarcation of areas based on homogeneous data remain subjective because of the
continuum of spatial elements. Nevertheless, the fundamental finding maintains, the space-time continuum on Earth's surface
can be investigated—as has been demonstrated—by several analysing methods. 相似文献
13.
Beyranvand Azar Azizi Ghasem Alizadeh-Choobari Omid Darvishi Boloorani Ali 《Natural Hazards》2019,98(1):229-249
Large near-field tsunamis pose a significant threat to the Canadian West Coast due to its proximity to the circum-Pacific belt where a significant tsunami-inducing earthquake event from the Cascadia subduction zone is expected. This study investigated the risks associated with such an event in terms of pedestrian evacuation needs and plans for the Town of Tofino, a small community located on the West Coast of Vancouver Island. The population-at-risk within the hazard zone and its ability to evacuate to safety is evaluated using anisotropic path-distance modelling. Mitigation measures, such as vertical evacuation buildings, are quantitatively evaluated. Site-specific inundation modelling was not performed as part of this study; tsunami hazard and safe zones were computed using a range of run-ups varying between 3 and 25 m. It was established that up to 80% of the population is within the maximum hazard zone considered. This evacuation modelling exercise indicates that a maximum of 13% of the population would have insufficient time to reach safety when using a mobility-impaired ambulatory speed. The use of three vertical evacuation buildings can reduce the risk of losing population in this category by 99%. Although some conservative assumptions were used (vertical datum at higher high water, reductions in safe zones by generalization process and mobility-impaired evacuation speeds), the evacuation potential is likely overestimated due to the coarseness of the topographic data used in the evacuation modelling and from an overestimated first wave arrival time. This is the first Canadian study which used anisotropic evacuation modelling to evaluate the vulnerability of a Canadian community to tsunami inundation.
相似文献14.
The Last Picture Show does not fall within the genre of the Western, yet the cinematic narrative mourns the loss of the iconic Westerner — a man
— and the passing of his home places that constitute the Old West. This paper is concerned with the ways in which this man
and his places are transformed along with the embryonic but inexorable emergence of the New West — and its attendant demand
for recognition of hitherto unheard voices (e.g., women, Latinos) — that accompanied significant social, cultural and political
shifts that were beginning to emerge within the country as a whole in the represented early 1950s. His represented sites of
contestation are found within the frame of the small west Texas town of Anarene, created by Larry McMurtry's novel of the
same name as the film, both of which reflect contexts of the era in which they were constructed — the mid 1960s to early 1970s.
We suggest that the film shows a great sensitivity to the ways in which particular masculinities are constituted in specific
places, to the tensions that arise from the changing nature and definitions of masculinity as they are linked to these places,
and with his sense of nostalgia and loss that accompanies his inevitable decline. But there is no clear and empowered place
for women in these new places, only a recontextualized form of a patriarchal order which is not relational and which still
maintains essentialist assumptions of gender. The Old West has taken new shape, much to the chagrin of man, but it is hardly
a New West, with its emerging and representative voices.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
In order to explore the consequences of precipitation increase on soil erosion in Uruguay, the monthly Fournier Index (FI) and the annual Modified Fournier Index (MFI) were developed as a preliminary approach, covering consecutive decadal periods from 1931 to 2000. Rainfall data were used
from 13 stations distributed all over the country. MFI shows a decrease in the 1940s, an increase during the 1950s, then a little decrease during the 1960s and 1970s and an increase
in the 1980s, remaining near these last values during the 1990s. FI behavior in July and October in the last two decades shows a decrease in the Northeast region of the country—the region with
highest annual precipitation—and a slight increase over the Southeast—the region with the lowest annual precipitation and
the only region with a winter rainfall maximum. For the core months of winter and early spring there is a decline in erosivity
in the Northeast, but an increase in the Southeast. January shows erosivity decreasing in the South during the last two decades.
In April there is a peak in precipitation variability all across the country. FI shows an early increase during the 1940s in the Northwest, and generally very low values during the 1970s, with the return
of high values in the 1990s, especially in the Northern corner. Results pose a challenge in order to improve research on the
erosion problem, since the main source of freshwater nationwide remains surface river flow, which is prone to higher turbidity
problems in areas of high soil erosion. 相似文献
16.
Emphasis has been given to a number of aspects which characterise technological development in today's economic systems and
which have an impact on the working environment and on gender differences. Technological change is leading to a strong divide
between knowledge “producers” and “users”. The possibility of access to one or both knowledge systems indicates the extent
of women's participation in the economic and spatial transformations brought about by the new technologies. This research
aims to analyse the development of new technologies and the presence of the female workforce in the field of new knowledge
generation, and also to verify gender-related conditions in learning and using new technologies. In particular, an analysis
has been carried out of the empirical case study of Pisa, a point of reference for comparisons with other Italian and European
cases. The research focuses on: the examination of women's capabilities in the field of new technologies through the analysis
of University training courses; the analysis of women's presence and status among the university staff, especially in science
and technology; a detailed survey of female employment in innovative sectors. The results of the research emphasise the gender
perspectives of inclusion — as regards the application of technologies — and exclusion — as regards the generation of knowledge
— of women in or from new technologies. At the same time, the research stresses the growth of women's roles in this sector
during recent years and, by reconstructing life histories, underlines the conditions and difficulties that have been met by
women entering these new types of employment.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Many physico-chemical variables like rock-type, climate, topography and exposure age affect weathering environments. In the
present study, an attempt is made to understand how the nature of clay minerals formed due to weathering differs in tropical
regions receiving high and low rainfall. Clay mineralogy of weathering profiles in west coast of India, which receives about
3 m rainfall through two monsoons and those from the inland rain-shadow zones (<200 cm rainfall) are studied using X-ray diffraction
technique. In the west coast, 1:1 clays (kaolinite) and Fe—Al oxides (gibbsite/goethite) are dominant clay minerals in the
weathering profiles while 2:1 clay minerals are absent or found only in trace amounts. Weathering profiles in the rain shadow
region have more complex clay mineralogy and are dominated by 2:1 clays and kaolinite. Fe—Al oxides are either less or absent
in clay fraction. The kaolinite—smectite interstratified mineral in Banasandra profiles are formed due to transformation of
smectites to kaolinite, which is indicative of a humid paleoclimate. In tropical regions receiving high rainfall the clay
mineral assemblage remains the same irrespective of the parent rock type. Rainfall and availability of water apart from temperature,
are the most important factors that determine kinetics of chemical weathering. Mineral alteration reactions proceed through
different pathways in water rich and water poor environments. 相似文献
18.
Wang Hongmei Ma Xiangru Liu Deng Yang Xiaofen Li Jihong 《Frontiers of Earth Science》2007,1(4):399-404
Understanding the dynamics of organic matter in modern marine water columns greatly favors the geobiological evaluation of
hydrocarbon source rocks. Biolipids could make great contribution to petroleum hydrocarbons due to their comparable chemical
components and the slightly refractory characteristics of biolipids during the microbial/thermal degradation. A variety of
environmental factors such as temperature, CO2 and salinity could affect the biochemical contents in microorganisms. As a result, microorganisms living in a changing environmental
condition might have a different contribution to the petroleum formation. Organic carbon flux is shown to bear a positive
correlation with the primary productivity only within a certain range of biomass volumes in a specific biohabitat. Furthermore,
organic matter is degraded much quickly in a water column with oxic conditions. Therefore, the anoxic condition, along with
the enhanced biological productivity, would be one of the significant factors in the formation of high-quality hydrocarbon
source rocks. The formation of biofilms and microbial mats favors the preservation of sedimentary organic matter by decreasing
the degradation rate of organic matter. Identification of biofilms and microbial mats in sedimentary rocks will thus greatly
help to understand the depositional processes of organic matter finally preserved in hydrocarbon source rocks.
__________
Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 748–754 [译自: 地球科学—中国地质大学学报 相似文献
19.
With the help of aerial photographs, satellite photographs and imageries, contour maps, geological and geomorphological information
(personal correspondence and unpublished works), geophysical regional data, and field work, it has been possible to map a
network of fractures, alignments, and faults in 26 areas (distinguishing them quantitatively and hierarchically). Links with
known regional structures were also studied. Interpretation of the linear relief elements confirms the very different density,
dimensions, strikes, and function of the fracturation and also, from a microtectonic perspective, explains the activity of
some active faults better. It has confirmed some previous results and improved on others; for example, the Oriente fault which
is the most active in Cuba with two segments (Western: Cabo Cruz—Santiago de Cuba; Eastern: Santiago de Cuba—Punta de Maisí,
the Western fault being the most active); the Nortecubana fault, forming the northern limit of the Cuban megablock, and divided
into three segments; and the Cauto—Nipe fault, forming the limit of the neotectonic units, presenting two segments with three
seismoactive knots. 相似文献
20.
Systematic GIS-based landslide inventory as the first step for effective landslide-hazard management 总被引：1，自引：1，他引：1
The purpose of the so-called IFFI project (Inventario dei Fenomeni Franosi in Italia—Inventory of Landslides in Italy) and of many other related activities carried out by the Centro Regionale per le Ricerche Territoriali e Geologiche of ARPA Piemonte (Agenzia Regionale per la Protezione Ambientale—Regional Agency for Environmental Protection), is to map all the existing landslides in Piemonte (including both results of monitoring data and available historical data). ARPA carried out new systematic surveys using
airphoto interpretation and created a specific alphanumeric geological information systems (GIS)-based database to store and
process all the collected data. In order to obtain proper landslide-hazard zoning, it is necessary to provide a landslide
inventory and to define the relationship between landslides and geological setting. A landslide inventory represents a fundamental
base of knowledge, is a very basic tool for land planning, and strongly helps the local authorities in their decision making. 相似文献